If you’re a health-conscious person, then you’re probably concerned about GMOs in your diet. While the proponents of GMOs are quite adamant that consuming genetically modified organisms has been proven safe, some members of the scientific community aren’t quite so sure.

One matter of concern for GMO critics is that the studies used to justify their introduction into the U.S. food supply have been inadequate at best, and that the long-term health effects of consuming genetically modified organisms are still an unknown variable.

A study conducted in 2012 by Earth Open Source, a non-profit dedicated to ensuring the safety and sustainability of the global food system, suggested that GM foods pose significant and largely overlooked health and environmental hazards. This study is by no means the only one to imply that the data used by Big Biotech to deflect criticism is nowhere near ironclad.

Another issue is that GMO manufacturers are adamantly opposed to initiatives that would require products containing GMOs to be labeled as such. With absent labels, it’s difficult to trace which products contain them, making the gathering of data on the long-term effects of consuming them nearly impossible.

The absence of GMO labels on the majority of the food supply in the U.S. also makes it difficult for consumers to avoid them, a situation that GMO producers have a vested interest in maintaining.

In fact, many members of the U.S. population are consuming genetically modified material on a daily basis, without any knowledge of it. So, just how common are GMOs in the U.S. food supply?

Most Common GE Crops

Certain foods are much more likely to be genetically modified than others. Soybeans are the most common GM crop, followed by corn, canola, cotton, sugar beets, alfalfa, Hawaiian papaya, zucchini, and yellow crookneck squash.

Nearly 9 of every 10 soybeans produced in the U.S. are genetically engineered, so unless your edamame, tofu, or tempeh is specifically labeled as GMO-free or organic, then you’re probably eating GMOs.

More than 85% of the corn grown in the U.S. is genetically modified, as well. Both corn and soy are most commonly engineered to be resistant to the herbicide glycophosphate, also known as Roundup. It should come as no surprise that Monsanto, one of the largest producers of GMO seed, is also the maker of Roundup.

90% of the U.S. Canola crop is genetically modified. Canola is commonly used in cooking oils. More than 50% of the sugar sold in the United States contains sugar beets, 9 out of every 10 of which are genetically modified.

Most people think of clothing when they think of cotton, but cottonseed oil is used in a wide range of food products, from shortening to potato chips. Less than 6% of the cotton grown in the U.S. is non-GMO.

GMOs Are Widespread

It’s quite apparent that GMOs have found their way into a wide array of food products. Corn, soybeans, canola, cottonseed oil, or all of the above can be found in more than 70% of the processed food found on grocery store shelves.

Avoiding GMOs can be tricky, but it’s not impossible. Buying organic produce goes a long way towards eliminating them from one’s grocery cart and diet. Looking for the certified non-GMO label is another way to avoid them.

As a rule of thumb, if a vegetable is on the list of the 9 most common GMO foods and isn’t labeled otherwise, it’s probably genetically modified.

Many common health supplements even contain GMOs. To best avoid GMOs in, it is important to research and find out exactly how ingredients are cultivated. Pure Hawaiian Spirulina and Astaxanthin are powerful and effective supplements with no GMOs included in their ingredients.